Miami Children's Hospital
Local: 305-666-6511
Toll Free: 800-432-6837
My Kids Patient Portal
Search
Advanced Search

Pediatric Center
In this section

Care Guides

Anaphylaxis

  PRINT    
     Bookmark and Share

Anaphylaxis is the most severe type of allergic reaction and requires immediate medical attention. If not treated right away, anaphylaxis may cause shock or death.

What happens during anaphylaxis?

People who have allergies have higher levels of the type of antibody to a specific substance (an allergen) known as Immunoglobulin E (IgE). The anaphylactic reaction depends on previous exposure or "sensitization" to a particular allergen. During the first exposure, the body builds up allergen-specific IgE antibodies.

Upon re-exposure to the allergen, the IgE antibodies launch a whole-body (systemic) immune response. This can result in rapid loss of blood pressure. The heart may strain, and the brain may stop receiving oxygen flow. The vocal cords and other tissues may swell. The lungs can fill with fluid, and the airways may become severely constricted.

What causes anaphylaxis?

Substances that can cause anaphylaxis include:

  • Insect sting venom
  • Foods -- particularly shellfish, peanuts, other tree nuts, eggs, and milk
  • Medications -- especially antibiotics and contrast media used in computed tomography (CT) scans
  • Vaccines that contain egg protein
  • Latex
  • Immunotherapy solutions

People prone to anaphylaxis may have a history of food allergy, asthma, prior anaphylactic reactions, or other allergic reactions.

Symptoms

Anaphylaxis usually occurs rapidly, unexpectedly, and affects many parts of the body. Watch for the following symptoms:

  • Warmth, skin flushing, or hives
  • Tingling and swelling in the lips, feet, hands, or other body parts
  • Wheezing, whistling while breathing, or shortness of breath
  • Difficulty swallowing due to swelling in the throat
  • Lightheadedness or faintness
  • Palpitations or irregular heartbeat
  • Loss of consciousness or seizures due to low blood pressure

Other symptoms may include hoarseness, cough, chest tightness, sneezing, and gastrointestinal symptoms like bloating, cramps, nausea, vomiting, or diarrhea.

Emergency treatment

Seek treatment of anaphylaxis immediately to re-open the airways and regain normal blood pressure. If you or someone you're with is experiencing symptoms of anaphylaxis, call 911 for emergency medical treatment or go directly to the nearest emergency room. If you have an epinephrine pen, use it promptly.

At the hospital or treatment facility, you may have a blood sample taken for a "serum tryptase test," which will distinguish anaphylaxis from other types of reactions. You will receive a shot of epinephrine, or other anti-inflammatory medications like corticosteroids or antihistamines. Your vital signs will be monitored for several hours after the reaction -- anaphylactic symptoms can persist after treatment or return hours later.

Be prepared!

Stay away from allergens that you know you're allergic to. (Allergy testing can help you to determine specific allergens to avoid.) If you have food allergies, always read food labels, and keep a food diary. When you go to a restaurant, talk to the server about the ingredients in the food before ordering. Avoid stinging insects, if you can.

If you know you're prone to anaphylaxis, wear a medical identification bracelet or necklace to alert hospital and emergency personnel. Also, tell your friends, family members, and co-workers, and write out an action plan, so they know how to respond in case of emergency.

Always carry an injectable epinephrine kit (such as EpiPen or Twinject) in case of an anaphylactic reaction -- your doctor will show you how to give yourself the intra-muscular shot of epinephrine. This medicine will help you feel better, but you still need to be under medical observation until all your vital signs are back to normal.

Reference

The diagnosis and management of anaphylaxis: an updated practice parameter 2010. J Allergy Clin Immunol. Sept 2010;126(3):477-80.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial proces and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. ©1997- 2010 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.